1. Field of the Invention
This invention relates to tampon inserters, and is directed more particularly to tampon inserters which deposit a tampon in a body cavity by pulling on, or withdrawing, the insertion tube.
2. Description of the Prior Art
In the field of tampon inserters there has come into wide use the kind of inserter which may be characterized as the "push" type. These inserters generally comprise, in a simple form, a pair of coaxial hollow cylinders or tubes, the larger outer tube serving as an insertion tube and containing a compressed tampon at its proximal end, and the smaller inner tube serving as a plunger, which, when operated from the distal end of the insertion tube and moved axially along the insertion tube toward its proximal end, ejects the tampon from the insertion tube. A plunger seat may be formed at the proximal end of the inner tube, to insure better engagement with the tampon and more positive ejection from the insertion tube, and suitable structure may be provided at the distal end of the insertion tube to provide gripping means and thereby facilitate use of the tampon inserter.
It has been recognized that tampon inserters of the type described above have certain deficiencies which are readily apparent to many users of such devices. An important shortcoming is the variation in depth of placement of the tampon within the vagina. If placement is too shallow, pressure from the sphincter muscles against the tampon can cause discomfort, and accidental expulsion of the tampon is a further possibility. If placement is too deep, the tampon may extend into portions of the vagina, where, for reasons of the size and shape of that organ, complete contact between the tampon and the walls of the vagina is not maintained; this can lead to the so-called "bypass" problem, in which menstrual fluids can get by the tampon without being absorbed.
Another deficiency of the "push" type inserter described above is the discomfort experienced by a substantial portion of users when the plunger is operated to eject the tampon from the insertion tube. Unlike the outer surface of the insertion tube, which is purposely made smooth and somewhat lubricious for easy and comfortable insertion, the tampon usually has a rough and irregular surface, in part as a consequence of its design for absorptive properties, and shoving it out of the insertion tube against the delicate walls and folds of the vagina is frequently accompanied by discomfort due to the friction.
Controlling depth of insertion has been addressed in U.S. Pat. No. 702,570, which issued on June 17, 1902, and more recently in U.S. Pat. No. 3,753,437, which issued on Aug. 21, 1973. In both patents there is provided an annular collar or shield around the insertion tube at the proper distance from the proximal end of the insertion tube, in order to control depth of penetration of the insertion tube and, consequently, depth of placement of the tampon. However, no solution is provided to the above-mentioned friction problem.
One solution to the friction problem is shown in U.S. Pat. No. 2,155,285, which issued on Apr. 18, 1939, in which a tampon inserter is provided of a kind that can be termed the "pull" type. After insertion of the appliance into a body cavity, an inner retainer portion, which is analogous to a plunger means, is held stationary while an outer cylinder, analogous to an insertion tube, is pulled away or withdrawn, leaving the tampon behind, in place. The friction problem is thereby overcome, since, instead of pushing the tampon out of the inserter, roughly shoving it against delicate body tissues, it is located in its final position at the time when the appliance is inserted and is not moved in or out relative to the vagina when the outer tube is withdrawn. However this approach provides no solution to the above-mentioned insertion depth problem, because the user is not provided with any positive stop means, but must instead endeavor to hold the plunger means in fixed position while withdrawing the outer tube, a procedure which is readily subject to error and inconsistency.
If the tampon inserter described in U.S. Pat. No. 2,155,285, referred to above, were provided with a collar or shield around the outer cylinder, near the distal end, for example, in an attempt to control depth of insertion, little additional benefit would be realized, because the collar would be withdrawn from place along with the outer tube, when it is needed instead to provide a stationary position reference until after the tampon is deposited in its correct position. It is also to be recognized that known tampon inserters of the push or pull type have an inherent similarity in that the push type, if the plunger is provided with a long enough handle to allow maintaining a positive grip on it throughout use, can be operated in the same manner as the pull type, by pulling back on the insertion tube while holding the plunger firmly in place, instead of pushing on the plunger while holding the insertion tube in place.
It will be seen, then, that each of the above types of tampon inserter has its own advantages and disadvantages, and that neither has heretofore combined in one type the desired properties of both without the shortcomings of either.